# Find the integral of xlogx/(1+x^2)^2 under the limits 0 to infinity.

$int frac{xln left(xright)}{left(1+x^2right)^2}dx$ $frac{xln left(xright)}{left(1+x^2right)^2}=left(xln left(xright)right)frac{1}{left(1+x^2right)^2}$ $=int :xln left(xright)frac{1}{left(1+x^2right)^2}dx$ $mathrm{Apply:Integration:By:Parts:}:u=ln left(xright),:v’=frac{1}{left(1+x^2right)^2}x$ $=-frac{ln left(xright)}{2left(1+x^2right)}-int :-frac{1}{2xleft(1+x^2right)}dx$ $int :-frac{1}{2xleft(1+x^2right)}dx=-frac{1}{2}left(ln left|xright|-frac{1}{2}ln left|x^2+1right|right)$ $=-frac{ln left(xright)}{2left(1+x^2right)}-left(-frac{1}{2}left(ln left|xright|-frac{1}{2}ln left|x^2+1right|right)right)$ $=-frac{ln left(xright)}{2left(1+x^2right)}+frac{1}{2}left(ln left|xright|-frac{1}{2}ln left|x^2+1right|right)$ $=-frac{ln left(xright)}{2left(1+x^2right)}+frac{1}{2}left(ln left|xright|-frac{1}{2}ln left|x^2+1right|right)+C$

On computing the boundaries,
=0-0
0